Summary Of Significant Accounting Policies (Reclassification Out Of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Line Items]
Operating Revenues	$ 428,704	$ 502,624	$ 1,804,824	$ 1,750,900
Income Before Income Taxes	125,555	141,075	543,614	543,151
Income Tax Expense	(32,935)	(32,917)	(140,425)	(135,272)
Net Income Available for Common Stock	92,620	108,158	403,189	407,879
Amount Of Gain Or (Loss) Reclassified From Accumulated Other Comprehensive Loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Line Items]
Income Before Income Taxes	57,692	(298,371)	(120,590)	(591,180)
Income Tax Expense	(15,813)	81,663	32,967	161,803
Net Income Available for Common Stock	41,879	(216,708)	(87,623)	(429,377)
Amount Of Gain Or (Loss) Reclassified From Accumulated Other Comprehensive Loss [Member] | Commodity Contracts [Member] | Gains And Losses On Derivative Financial Instruments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Line Items]
Operating Revenues	57,842	(298,372)	(120,088)	(591,271)
Foreign Currency Contracts [Member] | Amount Of Gain Or (Loss) Reclassified From Accumulated Other Comprehensive Loss [Member] | Gains And Losses On Derivative Financial Instruments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Loss [Line Items]
Operating Revenues	$ (150)	$ 1	$ (502)	$ 91